Pipe liner

ABSTRACT

A pipe liner for lining an existing pipe. The pipe liner includes a first elongated portion of plastic material and a second portion extending from the elongated portion with a flexibility which is greater than the elongated portion. The additional flexibility assist the liner in its insertion through an existing pipe.

[0001] The invention relates to a pipe liner configuration.

[0002] In pipeline refurbishing (e.g. gas pipes) it is known to run a plastic liner pipe through an existing steel pipe. However there can be problems with insertion due to bends and other partial obstructions to the passage of the liner pipe.

[0003] According to the invention there is provided a liner pipe for lining an existing pipe comprising a first elongate portion of plastics material and including a second portion extending from the first portion and having a flexibility substantially greater than the first portion to assist in insertion through an existing pipe.

[0004] The second portion is preferably of corrugated construction.

[0005] The second portion preferably terminates in nose-cone configured to enable a seal to be formed between the liner pipe and the existing pipe and provided with stopper means temporarily to prevent fluid flow into the liner pipe.

[0006] The invention will be described with reference to the accompanying drawing.

[0007] In the FIGURE a nose-cone 10, is welded onto corrugated pipe portion 11. The nose-cone 10, is of flexible plastic material e.g. polyethylene. The radial Vanes 12, form a seal between the two pipes 15 and 16, as the liner pipe is pushed down the service pipe 16, to be lined. A stopper 15, of plastic (e.g. in disc form) is inserted into the nose-cone 10, to prevent gas entering liner pipe 15, while it is being pushed along the pipe 16 to be lined.

[0008] The corrugated leading section 11, of the pipe 15, is welded to an elongated portion 14, which is of a more rigid polyethylene construction which forms the major length of the inserted pipe 15.

[0009] When the liner pipe 15 is in position a rod (not shown) is inserted down the bore of the liner pipe 15 from the right-hand side to push the stopper 13, out and let gas enter the liner pipe 15. 

1. A liner pipe for lining an existing pipe comprising a first elongate portion of plastics material and including a second portion extending from the first portion and having a flexibility substantially greater than the first portion to assist in insertion through an existing pipe.
 2. A liner pipe as claimed in claim 1 wherein the second portion is of corrugated construction.
 3. A liner pipe as claimed in claim 1 or 2 wherein the second portion terminates in a nose-cone configured to enable a seal to be formed between the liner pipe and the existing pipe and provided with stopper means temporarily to prevent fluid flow into the liner pipe.
 4. A liner pipe as claimed in claim 3 wherein the seal includes radial vanes.
 5. A liner pipe as claimed in claim 3 or 4 wherein means are insertable to co-operate with the stopper to move the stopper to allow fluid flow to restart.
 6. A liner pipe substantially as described herein with reference to the accompanying drawing. 